Cemex to lay off at least 70 workers at Lyons cement plant starting Nov. 21

Cemex will lay off at least 70 workers at its cement plant in Lyons beginning Nov. 21, according to a WARN Act notice filed with the Boulder County Attorney's office.

The notice, filed Sept. 22, says the cuts will affect at least 70 employees and was signed by a company vice president, Boulder County spokesperson Gloria Handyside said.

Cemex did not say whether the plant's kiln would keep running. In response to questions, company spokesperson Randy Stuart said the layoffs would reduce staffing at the Lyons plant but would not end cement sales and distribution there.

"Cemex will be rebalancing staffing levels at its Lyons cement plant beginning in the fall 2026, resulting in the elimination of some positions," Stuart said in an email. "Although positions will be eliminated, cement sales and distribution at the Lyons plant will continue."

In a follow-up question about the kiln, Stuart said, "The cement operation at Lyons is not ceasing."

The plant is one of the largest industrial sites along Highway 66 between Longmont and Lyons. It includes cement manufacturing and a trucking and distribution center for cement and cement-making materials.

The number of people who remain at the plant after the cuts depends on which employment figure is used. Sarah Lorang, a neighborhood activist who has pushed for tougher enforcement or closure, said a filing with the Mine Safety and Health Administration lists 112 people employed at the plant.

In recent negotiations and legal proceedings with Boulder County, Cemex has said more than 100 people work at the site. In a 2023 flyer describing the plant's capabilities, the company said it employed 90 people.

The state labor and employment office had not yet posted the Cemex WARN notice on the spreadsheet it keeps of such layoff filings.

Lorang said the size of the layoffs raised questions about how the facility will operate with fewer staff.

"We have a lot of questions," Lorang said Wednesday. "With layoffs of this size at a facility this large, our biggest concern is safety, for the employees and for the surrounding community. Will Cemex be running the kiln with a skeleton crew? What will day-to-day operations actually look like? Given the plant's safety and environmental record, we think the community deserves real transparency about what this next chapter looks like."

The layoffs follow years of local conflict over the plant's mining, truck traffic and emissions. Cemex's high-temperature kilns rank among the largest industrial sources of greenhouse gas emissions in Colorado, and neighbors have complained about dust from yard activity, trucking and heavy traffic on Colorado 66.

The company once tried to extend its mining operation on the north side of the highway by offering to donate significant acreage of open space in exchange for longer permits. Community groups and some local officials opposed the trade. Boulder County rejected the swap and shut down the mining side of the operation, though Cemex kept producing cement at the kiln using trucked-in materials.

The county's planning director then ordered the kiln shut down, saying Cemex had violated land-use permit terms because of increased traffic from bringing in outside materials.

Cemex appealed, and Boulder County Community Planning and Permitting Director Dale Case rescinded the termination notice in May. Case said previous studies had overstated truck traffic to and from the plant on Colorado 66.

Cemex's position in the Colorado cement market is smaller than it once was. The Lyons kiln is one of only three major cement-making operations in the state. Eagle Materials recently expanded its cement factory in Laramie, Wyoming, and added a distribution facility in northern Colorado.